Stark and Wang estimate that in 1980 there were 10 million Christians in the People's Republic of China, and that in 2007 the figure was 60 million. These numbers yield an annual growth rate of 7 percent – which means that last year, there were nearly 100 million Christians in China.

They hold that this large increase in the number of Christians in China is driven by the conversion of the better educated, who are experiencing “cultural incongruity” between traditional Asian culture and industrial-technological modernity, which results in a spiritual deprivation, which Christianity is able to answer.

China's intellectuals, Stark told CNA Aug. 14, “are very convinced they've got to turn West to understand the world they live in … and they're convinced by my argument that eastern religions don't fit the modern world they're engaged in, and that they need to look to the West to find philosophies and religions. It's quite amazing.”

Eastern religions, like Taoism, Confucianism, and Buddhism, Stark maintained, “are all anti-progress; they all proclaim the world is going downhill from a glorious past, and that we should look backwards, not forwards. None of them admit that we're able to understand anything about the universe – it's something we have to meditate on, not something to try and theorize about, as the physicists and chemists do. And that doesn't fit with the world that modern Chinese are experiencing having happened around them.”

“Industrial society, and all the science it's based on, doesn't fit well with those kind of religious views,” Stark reflected.

“But the question of what does the world mean, and how do we live in it, persists – and so that's a major motor in the Christianization of China, and it explains why it's the most educated Chinese who are the most apt to join.”

The spread of Christianity in China, he said, has been possible even “during the worst time of Chinese persecution” under Mao Zedong's cultural revolution of the 1960s and 70s because “this process of conversion is invisible; the government can't see it.”

According to Stark, religious conversion occurs primarily through social networks, and so is “invisible” to government officials. He holds that Chinese living in rural areas are more likely than city dwellers to be Christian, because their social ties are stronger, and thus Christianity can be transmitted there more easily.

Revivalist tent meetings, he said, “is not really how it's done…People join things in a much more intimate, a much quieter way.”

Catholic missionaries have been in China since the Jesuits of the 16th century, and in 1949 – when communist forces gained control over the whole of the mainland – there were some 5,700 Catholic foreign missionaries, and a total of nearly 3.3 million Catholics.

The communist government of China expelled foreign missionaries, and later established the “Chinese Patriotic Catholic Association,” a government-sanctioned Catholic Church. This has existed in opposition to the 'underground' Church, which is persecuted and whose episcopal appointments are frequently not acknowledged by Chinese authorities.

Bishop Zhang was approved of by both the Chinese government and the Holy See – the appointment of bishops has been the two states' most prominent area of contention throughout the past 60 years, so their agreement is of some import.

“That was a very big deal,” Stark said, “because that's been the whole basis of Catholic persecution since the 1950s: that there were to be no trekking with religion that had any external, foreign ties; and the Protestants of course could and did accept that very easily, but for Catholics, the whole business of rejecting Rome wasn't really on, although some Catholic bishops at least pretended to do that – although it's not clear that they really did … I think this is very, very big news.”

The last episcopal consecration before Bishop Zhang's had ended in icy relations between the Vatican and China: in July 2012, Bishop Thaddeus Ma Daqin – who had been part of the Patriotic Association – announced shortly after his consecration that he was leaving the association. He was subsequently confined by the government.

Stark suggested that because of the agreement between Beijing and Rome on Bishop Zhang's nomination “there's no reason now that the Catholics have to be at all be underground; they can now all be part of the above-ground Church.”

“It was also made very, very clear in all the press releases that he had been pre-approved by the Pope. And consequently he violates that part of the Association's rules, and the government is condoning it; which means in a sense, the end of that particular government-controlled, non-standard Catholicism. The fact of the matter is that most of the people in that Church were real Catholics – they just pretended. I mean there was a lot of contact with Rome on the sly, but this is coming right out in the open, and I think it's very important.”

Stark affirmed that the change in the past three years – from the consecration of Bishop Ma to that of Bishop Zhang – is a huge change, adding, “I was extremely surprised by it.”

“But the fact is, the Communist Party is fairly deeply involved in Christian growth, in ways that are not talked about – but out in the villages, many of the local communist leaders are very openly Christian, to the point of having crosses on their doors, their living room walls, which is hardly being discreet about it.”

“In the cities it's more discreet, but still, in all there are enormous numbers of sons and daughters of communist officials who are now Christians, and you go to their elite university campuses, and it's shocking, the Christian feel of the place, in a way that you don't get in American, Christian colleges. You don't get this feeling at Notre Dame, or at Texas Christian, that you get walking around the University of Peking.”

He noted that there are many Christian professors, and that Christianity is strongest at the universities – where the future members of the country's Communist Party are studying.

“This may be part of what's going on behind the scenes,” Stark supposed: “that it's becoming uncomfortable to push Christianity around.”

Stark then noted that this is not the case in one of China's 34 province-level administrative divisions. In Zhejiang province, churches have been ordered to stop displaying crosses, and a number of churches have been demolished. Seven Christians have also been detained in that province.

Stark suggested that this persecution, localized as it is, may be because “the head of that province might be some communist who's in rebellion, if you will, against the loosening of reservations in the rest of the country.”

This loosening of reservations is notable – Stark reflected that “this whole notion of an underground church is very peculiar, since some of these 'underground' churches are four stories tall, and have crosses all over them. They're underground only in the sense that they don't have legal sanction – but they sure aren't hidden.”

In light of this new openness to Christianity across China as a whole, Stark supposed a continued 7 percent annual rate of growth of the religion. At that rate, there will be 150 million Christians in China in 2020; 295 million in 2030; and 579 million in 2040.

“The growth might stop: you never know what's going to happen in the future,” Stark said. “But at the current rate, there'll be a whole heck of a lot of Christians in China awfully soon.”